When a cartridge is fired in a firearm the powder in the cartridge is ignited by the primer and as the powder burns it generates gases that propel the bullet out of the cartridge case and down the barrel of the firearm. Normally, most of these gases leave the bore of the barrel of the firearm after the bullet exits the bore since the rear of the barrel is sealed during the firing process by the cartridge case which expands outward under the pressure of the gases to seal the chamber area of the barrel.
With certain firearms a portion of the gases in the bore of the barrel are used to open the action of the firearm. In such cases there is usually a port or hole along the barrel that permits a portion of the gases to be directed outside of the bore of the barrel. These gases either impinge upon a part, usually called an operating rod, that serves to unlock the breech of the firearm or are fed via what is usually called a gas tube to what is called a bolt carrier where the gases exert a rearward force upon the bolt carrier that results in unlocking the bolt and causing it to move to its open rearward position. In the M-16 or M-15 family of firearms, the bolt carrier also has a part called the bolt carrier key for receiving the gases from the gas tube. In this latter type of operation this results in gases in and around the bolt carrier in the receiver that need to be dispersed.
In the well known M-16 or AR-15 family of firearms, two holes are provided in the bolt carrier that are designed to vent gases within the bolt carrier outward and away from the receiver area of the firearm. However, these holes in practice do not vent all of the gases outside of the receiver and in addition a certain amount of gases are dumped into the receiver of the firearm when the bolt carrier key with its gas hole moves rearward away from the rear portion of the gas tube when the bolt carrier is pushed to the rear under gas pressure. This gas tends to travel to the rear of the receiver along the paths created by the charging handle and its associated pathway in the receiver. Since the rear portion of the charging handle is located near the eyes of the shooter this has the undesirable and dangerous effect of diverting gases into shooter's eyes which can cause eye damage or at least interfere with the shooter's ability to see properly and hence shoot accurately.
As might be expected, this undesirable and potentially dangerous gas situation becomes even more severe with a firearm that is fired fully automatically. It has also been determined that the dangerous gas situation is severe in suppressed firearms.
In the past there have been various attempts to remedy or alleviate this undesirable and dangerous problem. These have included the use of silicone rubber seals and the addition of baffles. Unfortunately, gas and heat resulted in the eroding away of the silicone rubber seals and baffles have a tendency to fall off the receiver of the firearm.
This invention eliminates the undesirable and dangerous problem of gas near the eyes of the shooter. With this invention, the gas in the vicinity of the firearm charging handle is controlled and is diverted away from the eye region of the shooter. This is also accomplished without any modifications to the basic firearm by a simple substitution of a new charging handle that is fully compatible with the existing firearm receiver and other associated parts. With this new charging handle the gas is both diverted and the eyes of the shooter are also shielded. In addition, the new charging handle also has provisions for making it easier to be operated by the shooter.